I think you've got everything you need here for a great 30 minute game.

The premise succeeds because it asks a simple question ("What are these people hiding?") and promises to deliver the answer quickly. That kind of direct setup / payoff captures my interest in a way most premises don't, because "What's going to happen?" is always more interesting than, "Here are some awesome characters, they do some stuff."

The limited art adds to the game instead of detracting from it. I don't think this story would work with character art. By using background images of the sky, the player is forced to rely on what the characters are saying to divine their intentions and personalities rather than relying on portraits for shorthand. This cuts out pre-made assumptions on the player's part. I had a sense that the player was looking through the eyes of the characters as they stared up at the sky, which made me feel close to them in a way that seeing them on screen wouldn't allow for.

The music is soothing, but also just a bit...off, with a melancholy kind of inevitability. Together with the disembodied perspective of the player, it creates a surreal feeling, and a tension.

I notice that you keep the gender of the characters ambiguous by using unisex names and avoiding pronouns in the game description. Interesting choice. I assumed at first that they were both gay, which I thought was an unusual coincidence for two strangers, then I remembered that those were names used by both men and women, and it drove home the point of just how little I knew of these people.

The major problem right now is the grammar. I think the dialogue is solid enough, but it is riddled with errors and awkward turns of phrase. If this were a finished game, I'd turn it off after the first few sentences for that reason alone, but that's something that can be proof read and edited.

I think this has a lot of potential if you can clean up the writing and deliver on the tension you've set up.